Grinding wheel knife sharpening attachment



July 31, 1951 r K. T. KELLER 2,562,618

GRINDING WHEEL KNIFE SHARPENING ATTACHMENT Filed Sept. 3, 1947 Patented July 31, 1951 GRINDING WHEEL KNIFE SHARPENING ATTACHMENT Kaufman T. Keller, Detroit, Mich., assignor to Chrysler Corporation, Highland Park, Mich., a

corporation of Delaware Application September 3, 1947, Serial No. 771,869

4 Claims.

My invention relates to grinding wheel attachments and more particularly to grinding wheel knife sharpening attachments.

The main object of my invention is to provide a grinding wheel with an attachment for guiding the motion of the blade over the surface of the grinding wheel.

Another object of my invention is to provide the attachment with a roller which is rotatable while in contact with the grinding wheel to further guide the motion of the blade over the surface of the wheel.

A further object of my invention is to provide means for yieldably urging the roller and a blade or other work against the periphery of the grinding wheel so as to govern the pressure with which the work is applied to the grinding surface.

Another object of the invention is to provide a pressure roller of this kind which readily picks up grit from the grinding surface of the wheel and so applies it in an abrading manner to the side of a blade opposite from the side operated upon by the grinding wheel as to remove the wire edge which is usually formed on a blade during sharpening operations.

Still another object of my invention is to provide the attachment with adjustable means for of the grinding wheel and work holding andguid ing attachment illustrated inFigs. 1 and 2.

' The work holding and guiding attachment illustrated in the drawing comprises a bracket 4 which is mounted and secured on the reduced threaded ends of a pair of vertical upright supports 5 one of which is shown in Figs. 1 and 3. by a pair of nuts 6. The other extremity of each support 5 may be mounted on the stationary structure of the grinding wheel, not shown. The bracket 4 is provided with a pair of outwardly extending flanges 1 and 8 which are provided with apertures 9 and III. A U-shaped member II has a pair of flanges I2 and [3 which have a sleeve i4 welded between their inner surfaces. The flanges l2 and 2 l3 as well as the sleeve ll have aligningapertures l5, l6 and I1, respectively, disposed therein, The outer surfaces of the flanges l2 and [3 engage the inner surfaces of the flanges 1 and 8 in such a manner as to align the apertures 9, l5, I6, I! and III for receiving the rod or shaft IS. The sleeve I4 is secured by the pin 18 to the rod l8 which is rotatable in the flanges l and 8 thereby allowing a pivotal motion of the U-shaped member H. The rod l8 extends outwardly through the flange 8 to receive a crank 28 and is secured to it by a pin 30. The U-shaped member II has a trunnion [9 extending from its bight portion on which is journaled a box-like structure 20. The box-like structure 20 is shiftable axially of the trunnion l9 and has the limits of its linear motion defined by the bight portion of the, U- shaped member II and a nut 21 mounted on the end of the trunnion I 9. Thepivotal axis of the box-like structure 20 is substantially normal to the shaft l8. This provides a universal joint action. 'Journaled between the side members 22 and 23 of the box-like structure 20 is a metal roller 24 which rests'upon the periphery 25 of the grinding wheel 26. The roller 24 is yieldably urged toward the periphery 25 of the wheel 26 by a spring 21 which has one extremity connected to the crank 28 which is fixed to the protruding end of the shaft I8 and its other extremity con-' nected to a stationary arm 29 mounted on the bracket 4 by screws 31. The weight of the roller 24 and the pivotally mounted structure on which it is journaled may be relied upon, in the absence of the spring 21 to urge the work against the wheel in some applications, but it is preferable to resiliently urge the roller toward the periphery of the wheel by a spring or other resilient means in most applications of the device.

Provided on the forward side of the box-like structure 20 is a lug 32 which has journaled therein a threaded pin 33. The lower extremity of the pin 33 is provided with a ball member 34 which is shiftably received within a, bladehold ing block generally designated by the numeral 35. The blade holding block has a slot 36 for receiving a blade and is provided at its upper portion with a ball seat member 31. The ball member 3c is adjustably fitted to the ball seat member 31 by means of a threaded element 38. The vertical motion of the threaded pin 33 is regulated by means of the threaded nuts 39, one of which is disposed above and below the lug 32, respectively.

During the operation of this device the blade is moved back and forth transversely of the wheel while the cutting edge of the knife is urged into the generally V-shaped space between the periphery of the roller 24 and the periphery of grinding wheel 26. The block 35 serves to properly position the blade with a pressure predetermined by the action of the spring 21. The roller 24 picks up grit from the grinding wheel and serves to remove any wire edge which tends to form. on the cutting edge of the blade during the operation.

It should be noted that an emery wheel may be used instead of a grindstone for ordinary operation, or a steel wheel may be used in place of the grindstone when it is not necessary to grind metal.

The blade holding block 35 may be conveniently removed together with the threaded pin 33 and nuts 39, if desired, in order to accommodate positioning of a. blade, or any other piece of work, by manual operation. When the blade holding block 35 is removed, the roller 24 still serves its intended functions of assisting in guiding a blade or piece .ofwork during movement of it across the periphery of the grinding wheel.

Although but one specific embodiment of the invention is herein shown and described, it will be understood that various changes in the sequence of operations, steps and materials employed may be made without departing from the spirit of the invention.

I claim: 7

1. Apparatus for positioning a blade relative to a grinding wheel comprising a support, a bracket carried by said support and having portions thereof defining a pivotal axis, a member mounted on said bracket and rotatable about the axis of said bracket, a frame structure, means mounting said frame structure on said member for rotation about an axis in a plane normal to said first mentioned axis and for linear movement in said plane, a cylindrical roller carried by said frame structure and adapted to frictionally engage said grinding wheel for rotation therewith, and means secured to said frame structure for holding said blade in engagement with said grinding wheel.

2. In grinding mechanism comprising a grinding wheel and means for supporting it for rotation; apparatus for positioning a blade relative to Fa ,ag rinding wheel comprising a support, a

bracket-partied by said support and having porti'olwthereof defining an axis, a member mounted bracket and rotatable about said axis, a

structure; means mounting said frame structur'efon said member for rotation about an axis in apiane'normal to said first mentioned axis and 'forlinear movement in said plane, a roller carried by said frame structure and adapted to frictiona'lly engage said grinding wheel for rotatimi therewith, 'a rod rotatably mounted L through said frame structure, and a blade holder 3. In grinding mechanism comprising a grinding wheel and means for supporting it for rotation; apparatus for positioning a blade relative to the grinding wheel comprising a support, a bracket carried by said support and having portions thereof defining an axis, a member mounted on said bracket and rotatable about said axis, a frame structure, means mounting said frame structure on said member for rotation about an axis in a plane normal to said first mentioned axis and for linear movement in said plane, a roller carried by said frame structure and adapted to frictionally engage said grinding wheel for rotation therewith, means secured to said frame structure adapted to hold said blade in engagement with the grinding wheel and said roller, a crank secured to and movable with said memher, and a spring for operating said crank adapted to yieldably urge said roller into contact with the grinding wheel.

4. In grinding mechanism comprising a grinding wheel and means for supporting it; apparatus for positioning a blade relative to a grinding wheel comprising a support, a bracket carried by said support having portions thereof defining an axis, a member mounted on said bracket and rotatable about said axis, a frame structure, means mounting said frame structure on said member for rotation about an axis in a plane normal to said first axis and for linear movement in said plane, a roller carried by said frame structure and adapted to frictionally engage the grinding wheel for rotation therewith, a rod shiftably mounted on said frame structure, a blade holder adjustably secured to said rod and adapted to hold saidblade in engagement with said grinding wheel, a crank secured to and movable with said member, and a spring for operating said crank and adapted to yieldably urge said roller into contact with the grinding wheel.

KAUFMAN T. KELLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name 'Date 31,461 Hyatt et a1 Feb. 19, 1861 348,497 Long Aug. 31, 1886 448,616 Hudson Mar. 17, 1891 853,958 Bowden-Smith May 21, 1907 941,529 Myers Nov. 30, 1909 977,172 De Vivo Nov. 29, 1910 1,357,956 Cooke Nov. 9, 1920 1,564,959 Holtzman Dec. 8, 1925 1,870,817 Maag et al. Aug. 9, 1932 1,870,818 Maag et a1 Aug. 9, 1932 2,161,992 Battocchi June 13, 1939 FOREIGN PATENTS Number Country Date 352,572 Great Britain July 16, 1931 635,580 France Dec. 29, 1927 

